4-Inch 140 Watts Coaxial Speaker System with additional voice coil ventilation for increased power handling and EXP pole core technology for maximum excursion and lower harmonic distortion. General: Cone Material: Injected PP. Surround: Rubber Tweeter: PEI Neodymium Magnet Frequency Response: 90-20,000 Hz. Sensitivity: 90dB. Mounting Depth: 39.5mm. Diameter: 100mm. Impedance: 4 Ohms Designer grilles